<!DOCTYPE html>
<html>

<head>
    <meta charset="utf-8" />
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <title>Page Title</title>
    <meta name="viewport" content="width=device-width, initial-scale=1">
    <style>
        label {
            position: absolute;
            top: 70px;
            left: 65px;
            font-size: 18px;
            opacity: 0;
            transform: translate(15px, 60px);
            transition: all 0.2s ease-in;
        }
        
        .blurlabel {
            opacity: 0;
            transform: translateY(1rem);
        }
        
        .focuslabel {
            /* background:#FF0000; */
            opacity: 1;
            transform: translateY(1rem);
        }
        
        .enabled {
            border: none;
            padding: 2px 12px;
            font-size: 18px;
            text-indent: 25px;
            line-height: 1.5;
            background-color: #fff;
            border-bottom: 1px solid #ccc;
            outline: none;
            box-shadow: 0px 0px 0px 0px;
        }
        
        input[type="text"]:focus,
        input[type="password"]:focus {
            border-bottom: 1.5px solid #26a2ff;
        }
    </style>
</head>

<body>
    <form>
        <label id="accLabel">账号</label>
        <input name="account" size="28" type="text" class="enabled text-info" placeholder="账号" />
    </form>
    <script src="node_modules/jquery/dist/jquery.js"></script>
    <script>
        $(":input[name='account']").on('focus', () => {
            $("#accLabel").addClass(
                "color", "red"
            )
        })
    </script>
</body>

</html>

</html>